The 52 year old was sentenced by Hove Crown Court.
Wayne Gavin Mathura, 52, of Roundstone Crescent, East Preston was convicted of 13 counts of rape between 2005 and 2009
He had been convicted at Hove Crown Court on 28 September of 13 counts of rape and sexual assault committed between 2005 and 2009 on the three girls who were aged 13 to 17 at the time. All three were known to him.
The prosecution followed an investigation by detectives from the West Sussex Safeguarding investigations Unit, working closely with West Sussex County Council Childrens' Services.
Detective Constable Simon Thorne, speaking on behalf of Detective Constable Jennie Hutchinson who jointly investigated the case said; "Mathura got to know the girls by seeing them in the street near his home, and through knowing some of their relatives. Over a period of time he systematically took advantage of their vulnerability and naivety and groomed them into a series of humiliating sexual encounters.
"This man is dangerous and preys on vulnerable women after gaining their trust. We hope that this sentence will prevent any other women ever suffering at his hands again, and will also most importantly encourage any other women who have been such victims to come forward to the police."
Anyone who wants to reports sexual offences against them can contact Sussex Police at any time online or by calling 101, and can arrange to talk in confidence to experienced investigators who can also arrange access to sources of further counselling and support.